Separating screen for overshot loader bucket



Sept. 25, 1956 J. R. AUSTIN, SR

SEPARATING SCREEN FOR OVERSHOT LOADER BUCKET Filed July 1 1954 INVENTOR. f fiawz-z United States Patent SEPARATING SCREEN FOR- OVERSHOT LOADER BUCKET John R. Austin, Sn, Denver, Colo. Application July 1, 1954, Serial No. 440,644 3 Claims, (Cl. 209-421) This invention relates to material handling apparatus and more particularlyto that type known as the overshot loader, whereby amaterial handling bucket is caused to be loadedaat the front end of avehicl-e, such as a tractor, and by theemployrnent of such structure, as pivoted arms to whichthe bucket: is attached the bucket-is caused to move over the top of the vehicle andbe unloaded at the rear thereof.

In. these overshot-loaders it may at times be desirable toseparate fine and coarse material being handled by the bucket .andto do it in an economical and easy manner during the operation of the loader. The primary object of my invention is to accomplishthese results.

Another object of my inventionis to. associate a screen? ing meanswith a bucket of an overshot loader that will separate coarse and-fine material during dumping operations by the bucket.

Yet-another object is to-so construct the screen and associate it with the-bucketthat the separated'material will b'e discharged at difierent distances-from the rear ofthe tractor when the bucket reaches dumping position.

2,764,292 Patented Sept. 25., 1.9.56

2 1 than the bottom section and extends at an obtuse angle to said bottom section. Between the two sections-areside walls 21.. The. bucket. may. be rigid or pivoted to the front cross member 11 of the yoke as indicated'at 22' and when pivoting isdone adouble acting hydraulic motor H is provided with its cylinder and piston pivotally con nected between the forwardend of the yoke and apoint on the rear section'of the bucketabove itspivot 22. The hydraulic lines to the. motors M and H are not shown as such is not believed to be necessary to-understand my invention. The motors M will be operated independently of themotor H and vice versa. With the motor H,,the bucket can be dumped at the front of the vehicle'when desired if the ,yoke.is..:raised somewhat or otherwise positioned onv the yoke for suchv operations as diggingand bulldozing.

With the'overshot loader structure just described, the bucket B can be placed in a down loading position at the frontof the tractor and loaded by moving-the tractor forwardly. Whenthe; bucket is down, the bottom sec? tion 19 of: the bucket will be substantially horizontal and loadingcan be easily accomplished. The bucket is. then raised up tothe position-shown in Figure 1- wherein the arms A are substantially vertical and the load in the bucket will be dumped by sliding on the back section and off thequnloadingiend thereof, all as" illustrated. The dumping of-the'bucket can occur alongside, of; a; truck TR having'a body'D thereon by. merely backing up the tractor'to the,truck,'all as illustrated;

In handling material; such as gravel and; sandnor dirt mixed with rocks, it. is,.often desirableto separate. the

A further object is to associate a screen separating meanswith an overshot loaderbucket in sucha manner that it -can be easily mounted inthe-buck-et andremoved when'desired. v Other objects of my} invention will become: apparent from the following description taken in-connectionwith the accompanying'drawings in which:

Figural is a side view of a ti-actor havinganovershot loader mounted thereon with the bucket of the loader'ha-ving 1 a material separating screen means embodying my in vention and being associatedtherewith, said loader'being shown backedupto a truck in material unloading-posh tion; and i Figure 2' is' a view looking down on the screen member and bucket asseen fromthe line 2--2-of Figure 1;

Referring to the drawings in detail, T indicates a tractor which may be of the track laying'typeas shown or of the wheeled type. Onthe frame F at opposite sides of the tractor are arms A (one only being shown) pivoted to the frame at-10 near the. rear driving members ,of. the track. The arms A are connectedtog ether at their forward end by'a cross member 11.to thus establish a yoke. At the" forward end of this yoke is mounted the bucket B of the overshot loader. The yoke and' bucket will be raised frornza down" loading position atzthe front of the tractor to the unloadingposition shown in Figure 1 by hydraulic motors M and lever arms 12 and 13. associated with each 'ann Aonthe'sides'ofthe tractor. Eachmotor has acylinder 14in which isa piston 15. having a piston rod 16. The cylinderispivoted atits. lower endto the frame at 17 and the piston rod ispivotally attached'to the connected ends" 18' of the lever arms 12 and "13 with the opposite end of the former pivotally connected to the front end of the yoke and the opposite end of the latter pivotally connected to the frame as shown.

The bucket B has a bottom loading section 19 and an unloading rear section 20. The rear section is longer coarse and fine material; I accomplish this; separating in an automatic. mannerxduring dumpingoperations by PTO, vidingascreen member's which asyshown; is arr-elongated screen 23 of suitable mesh held in' a frame 24 havingside walls, 252 As 'shown, the iscreenrmember is of considerably, greater length than the. back section. of the-bucket: and the. width of the-screen member is such as to'fit1withinz the Width of the. iIlSld610f the bucket: Thissc-reenmember has one end'attached. inside1of: the bucket. with such end positioned at; thezjunctu'rei of; the bottom andrear sections of? the; bucket. tight-against the back section or the'bottorn. section so that no material can pass betweenthe. said attached 'end and thebucket, but must. move'onto z the. screen i 23; The. attachmentto the bucketcanbevmade-with the side-:wallsby theuseof bolts 26- extenclingthrough the side walls of'the-rbucket and the frameofpthe-screen member:

Since.v the screen member islonger than the. back sec.- tionof the bucket, it will extend outwardly-beyond the unloading-edge ofsaid-back-sectiom The screen member is attached to the back section at its unloadingend and the attachment is made so the screenmemberwill beat an acute angle to the inside surface of the back section, thus leaving a space between the screen and. this inside surface of the back section so that material. falling through the screen can drop onto the back section and then freely flow along the, surface of the back section to the unloading edge and fall into the body of the truck 'orany-other placewhere the material is to be dumped: To-suppor't the free end of the screen on the dumping end of the bucket, there isprovided support braces 27 and 28 011 each sideof the screenmember; The braces 27 are connected from near the center of the screen member and the end of the back section of the bucket by 'suitablebolts '29 a d-s0. The braces 28 areattached to the-extreme "outer end of *thescreen member by-bolts 31 and then connected to the dumping end of the back section of the bucket by the bolts 30 which attach the brace 27 to the bucket. The braces 28 thus give support to the extreme outer end of the screen member. The outer end of the screen member has no end wall so that it will be free to discharge coarse material which will remain on the top of the screen and slide down the screen as the finer material which has been in the bucket passes through the screen and is dumped olf the unloading end of the back section.

In the preferred form of my invention, I desire to make the screen member S of such length that when the loader is being employed to load a truck body, such as the one illustrated, the coarse material which is separated from the finer material and is on the top of the screen will be able to be discharged from the screen member over the top of the truck body and into a pile alongside the truck, all as illustrated.

With the screen member constructed and mounted as shown, it will be seen that coarse material can be separated from fine material and this separating will be done automatically during dumping operations of the bucket. Not only will separation take place, but there will be a simultaneous discharge or dumping of both fine and coarse materials at different spaced points which will permit, as shown, the fine material to be discharged into a truck body and the coarser material discarded out on the ground beyond the truck body. Of course, the arrangement could be reversed if most of the material were coarse and it was desired to load this coarse material into a truck body. Then the truck would be positioned below where the coarse material was discharged from the screen and the finer material would pass through the screen and be discharged onto the ground between the back end of the tractor and the truck body. If it should be desired to load both the fine and coarse material, this could be done by having truck bodies positioned alongside of each other so the fine material would go into the closest truck body and the coarse material into the adjacent truck body which is farthest from the tractor.

It might be desired under some conditions to use the screen arrangement to screen out coarse material and then dump it at some other place besides farther beyond the finer material when the bucket is in unloading position. If such a condition were desired, the screen member S could be made shorter, and the side walls 25 thereof made higher. Also, the screen member could then have a rear wall so that coarse material going into the screen would be caught between the side walls and the end wall and held on the screen during discharge of the finer material from the back section of the bucket. After the finer material is dumped, the tractor could be turned and driven over to some selected place and the coarse material caused to be dumped out of the screen by a movement of the bucket on the arms under the actuation of the hydraulic motor H. In doing the dumping the arms would be lowered toward the front of the tractor and then the hydraulic motor actuated. Thisthen tips the bucket forwardly about pivot 22 on the arms and causes the coarse material held by the screen to roll back down to the bottom section of the bucket and then off the front edge thereof as the bottom section will be in an inclined position sutficient to cause dumping of the coarse material due to the. actuation of the motor H.

It will be noted that the screen member can be easily mounted in position in the bucket when desired to be used and also quickly removed, all by the detaching and attaching .of bolts. When the screen member is out, the overshot loader functions in its usual manner with both fine and coarse material discharged together.

I am aware that modifications are possible in the particular combination overshot loader bucket and screen means disclosed as embodying my invention and, therefore, I desire it to be understood that the scope of the invention 1s not to be limited except in accordance with the structural terms and equivalents of the appended claims.

What is claimed is:

1. In an overshot loader for vehicles having a bucket mounted for swinging movement from a forward loading position over the vehicle to a rear unloading position, said bucket having a bottom loading section which is substantially horizontal when the bucket is in loading position and a back unloading section extending upwardly and rearwardly from the rear end of the bottom section so as to be at an obtuse angle to said bottom section, and screen means mounted in said bucket for automatically screening material as it is dumped from the bucket and comprising a screen member extending at an acute angle to the surface of said back section and from a point on the bottom section of the bucket closely adjacent the intersection thereof with said back section to a point beyond the rear dumping edge of the back section of the bucket, so as to be spaced from the surface of the back section over at least a major portion of said surface so that material smaller than the screen member will pass therethrough before reaching the back section for unloading.

2. The overshot loader bucket and screen construction of claim 1 in which the screen extends such a substantial distance beyond the free unloading end of the back section that icoarse material held by the screen member can be unloaded off the extended end of the screen member simultaneously with finer material passing therethrough and being unloaded off the back section of the bucket but at a point beyond that of the finer material.

3. In an overshot loader for vehicles having a bucket mounted for swinging movement from a forward loading position over the vehicle to a rear unloading position, said bucket having a bottom loading section which is substantially horizontal when the bucketis in loading position and a back unloading section extending upwardly and rearwardly from the rear end of the bottom section so as to be at an obtuse angle to said bottom section; screen means mounted in said bucket for automatically screening material as it is dumped from the bucket and comprising a detachable screen member extending from a point on the bottom section of the bucket a substantial distance rearward of its forward edge to a point beyond the rear dumping edge of the back section of the bucket, so as to be spaced from the surface of the back section over at least a major portion of said surface so that material smaller than the screen member will pass therethrough before reaching the back section for unloading; said screen member extending such a substantial distance beyond the free unloading end of the back section that coarse material held by the screen member can be unloaded off the extended end of the screen member simultaneously with finer material passing therethrough and being unloaded off the back section of the bucket, but at a point beyond thatof the finer material; supporting rods between the unloading ends of the back section of the bucket and the screen member; said bucket being provided with side walls along the bottom and back section and said screen member being provided with side walls from a point where it extends beyond the side walls along said back section; and means for detachably connecting the side walls of said screen member to the side walls of said bucket.

References Cited in the file of this patent UNITED STATES PATENTS 1,398,666 Beach Nov. 29, 1921 1,593,447 Friedman July 20, 1926 1,611,860 Richey Dec. 21, 1926 1,675,092 Cipriano June 26, 1928 2,422,985 Reckler June 24, 1947 

